Physics-
General
Easy
Question
A composite rod made of three rods of equal length and cross-section as shown in the fig. The thermal conductivities of the materials of the rods are K/2, 5K and K respectively. The end A and end B are at constant temperatures. All heat entering the face A goes out of the end B there being no loss of heat from the sides of the bar. The effective thermal conductivity of the bar is
- 15K/16
- 6K/13
- 5K/16
- 2K/13
The correct answer is: 15K/16
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